Explain the phase in the life of the organism when it can reproduce sexually.

(N/A) Reproductive phase: When the reproductive system is mature enough to produce male and female gametes,the organism is ready to mate and reproduce.
This phase is called the reproductive phase.
Some major hormonal changes are exhibited during this phase.
In humans,the reproductive phase starts at about $12$ to $13$ years and lasts up to the age of $55$ to $60$ years.